The present invention pertains generally to model aircraft and, more particularly, to a model aircraft power pod which is releasably coupled with the model aircraft to initially power the model aircraft into flight and thereafter separate from the model aircraft.
Model aircraft enthusiasts, in particular, model glider plane enthusiasts, have for a long time been confronted with the problem of making their model aircraft air-borne. Up to now, various launching or take-off techniques have been tried, but these in general suffer from various limitations and possess undesirable features. For example, one already-known technique involves the use of a tow cable, one end of which attaches to a tow hook on the model aircraft. The cable extends for an appreciable distance along the ground, and the other end of the cable connects to a winch. The winch operates to wind up the cable and thereby cause the model aircraft to become air-borne after which time the cable is disconnected from the aircraft. This technique has at least several serious disadvantages. First, a relatively long, flat strip of ground, for example, several hundred feet, is required for set-up of the tow cable prior to take-off. Obviously, this involves the expenditure of a lot of time and energy for the set-up procedure. Second, since it is usually necessary that the model aircraft take off into the wind, the direction in which the tow cable is laid out is critical. If the wind should shift after the cable has been laid out, the operator must reorient the cable, assuming, of course, that the geographical terrain in the take-off area permits the cable to be conveniently reoriented. Needless to say, this procedure can at times try the patience of even the most devoted model aircraft enthusiast.
Another type of take-off arrangement has been proposed in U.S. Pat. No. 3,452,471 wherein a model stick glider is propelled into the air by means of a rocket motor pod. Although this arrangement is alleged to be capable of attaining vertical take-off, it has its own limitations and undesirable characteristics. One significant disadvantage is that an explosive ejection charge must be ignited to provide a rearward thrust to separate the rocket pod from the glider. Furthermore, the coupling between the rocket pod and the stick glider requires that the pod be bodily displaced upwardly and rearwardly relative to the stick glider before separation can occur.
The present invention is directed to a novel power pod for model aircraft, especially model glider planes, which overcomes the disadvantages of the prior techniques heretofore used in powering model aircraft into flight. With the present invention, a power pod is releasably coupled with a model glider to power the glider into flight and to thereafter separate from the glider by force of gravity without the need of any separate ejection charge and without the act of separation creating any undesired disturbance on the flight of the glider. Geographical considerations and wind direction are not critical, since the operator can easily aim the model aircraft in any desired heading at the time of takeoff. The power pod can be arranged to separate from the glider either upon exhaustion of the fuel supply contained within the power pod or at a later time upon command of a remote control radio signal. According to the preferred embodiments of the present invention, an adaptor element is fixedly attached to the glider fuselage, and the power pod itself is releasably coupled with the adaptor. An advantage of the adaptor is that it can accommodate a variety of different fuselage shapes without modification. Thus, the invention has the advantage of utility with a large number of currently available model aircraft. As a further feature, the invention provides a mounting arrangement for the engine on the pod which permits the direction of thrust to be set to an optimum angle relative to the glider fuselage. A still further feature of the invention resides in positive deployment of a parachute from the pod which is effected by means of a rip cord having a replaceable, breakable link. Such positive deployment of the parachute ensures that the pod safely descends to earth. The parachute is so attached to the pod that the pod descends in an orientation which substantially minimizes the risk of damage to the pod upon impact with the ground. The invention can be practiced with a variety of propulsion sources, although a small single-cylinder engine and propeller are preferably used. Several components of the preferred embodiments of the invention can be advantageously constructed from molded plastics thereby providing economical manufacture and ease of assembly.
As a result of the present invention, the model aircraft enthusiast is relieved of the complicated procedures and the limitations of the prior art arrangements. Accordingly, the present invention promotes maximum enjoyment for the model aircraft enthusiast in his hobby and removes the possibility of his being frustrated by the complicated and cumbersome set-up procedures.
The foregoing features and advantages of the invention, along with additional features and advantages, will be seen in the ensuing description and claims which are to be taken in conjunction with the accompanying drawings. The drawings illlustrate preferred embodiments of the invention in accordance with the best mode presently contemplated for carrying out the invention.